Top 10 Most Incredible Natural Phenomena Around The World

6. Sort Sol, Denmark

Sort sol is a nature phenomenon in the marshlands in southwestern Jutland, Denmark, in particular the marsh near Tønderand Ribe. Very large numbers of migrational starlings gather there in spring and autumn when they move between their winter grounds in southern Europe and their summer breeding grounds in Scandinavia and other countries near the Baltic Sea.

Sort sol takes place in the hours just after sunset. The birds gather in large flocks and form huge formations in the sky just before they decide for a location to roost for the night. The movements of the formations have been likened to kind of a dance or ballet and the birds are so numerous that they seem to obliterate the sunset, hence the term “sort sol” (Danish for “black sun”). Sort sol in the marsh near Tønder can occasionally comprise a formation with up to one million birds. Usually flocks break up when the number of individuals exceed about half a million birds due to excessive internal disturbances in the flock.